The present invention relates to nucleic acids and proteins encoded thereby. Invention nucleic acids encode novel Schwannomin-Binding-Proteins. The invention also relates to methods for making and using such nucleic acids and proteins.
The NF2 gene is the single most commonly mutated gene in benign tumors of the human nervous system. It is involved in the pathogenesis of virtually all schwannomas and many meningiomas (at least 50%) and ependymomas (Sainz et al., Hum. Mol. Genet. 3:885-891 (1994), Deprez et al., Am. J. Hum. Genet. 54:1022-1029 (1994), Rubio et al., Cancer Res. 54:45-47 (1994), Ruttledge et al, Nature Genet. 6:180-184 (1994), and Slavo et al., Cancer 64:243-247 (1995)). In addition to tumors, NF2 germline mutations also give rise to cataracts and retinal abnormalities such as hamartomas (Mautner et al., Neurosurgery 38:880-886 (1996)). The NF2 gene product is schwannomin (or merlin). Schwannomin is structurally similar to the ezrin-radixin-moesin (ERM) family of membrane-organizing proteins that link the plasma membrane and cytoskeleton (Rouleau et al., Nature 363:515-521 (1993) and Trofatter et al., Cell 72:791-800 (1993)). Schwannomin functions as a tumor suppressor, and as such is thought to have a role in a signal transduction pathway (Sainz et al., (1994), Huynh and Pulst, Oncogene 13:73-84 (1996), Tikoo et al., J. Biol. Chem. 269:23387-23390 (1994), and Twist et al., Hum. Mol. Genet. 3:147-151 (1994)). But other than its role in cell morphogenesis and adhesion (Huynh and Pulst (1996), supra), there is little additional knowledge of schwannomin function.
Therefore, there continues to be a need in the art for the discovery of additional proteins that interact with schwannomin, such as proteins that bind schwannomin in vivo, and especially a need for information serving to specifically identify and characterize such proteins in terms of their amino acid sequence. Moreover, to the extent that such molecules might form the basis for the development of therapeutic and diagnostic agents, it is essential that the DNA encoding them be elucidated. The present invention satisfies this need and provides related advantages as well.
In accordance with the present invention, there are provided novel isolated nucleic acids encoding Schwannomin-Binding-Proteins (SBPs). Further provided are vectors containing invention nucleic acids, probes that hybridize thereto, host cells transformed therewith, antisense-nucleic acids thereto and related compositions. The nucleic acid molecules described herein can be incorporated into a variety of expression systems known to those of skill in the art. In addition, the nucleic acid molecules of the present invention are useful as probes for assaying for the presence and/or amount of a SBP gene or mRNA transcript in a given sample. The nucleic acid molecules described herein, and oligonucleotide fragments thereof, are also useful as primers and/or templates in a PCR reaction for amplifying genes encoding SBPs.
In accordance with the present invention, there are also provided isolated mammalian SBPs. These proteins, or fragments thereof, are useful in bioassays, as immunogens for producing anti-SBP antibodies, or in therapeutic compositions containing such proteins and/or antibodies. Also provided are transgenic non-human mammals that express the invention protein.
Antibodies that are immunoreactive with invention SBPs are also provided. These antibodies are useful in diagnostic assays to determine levels of SEPs present in a given sample, e.g., tissue samples, Western blots, and the like. The antibodies can also be used to purify SBPs from crude cell extracts and the like. Moreover, these antibodies are considered therapeutically useful to counteract or supplement the biological effect of SBPs in vivo.
Methods and diagnostic systems for determining the levels of SBP protein in various tissue samples are also provided. These diagnostic methods can be used for monitoring the level of therapeutically administered SBP or fragments thereof to facilitate the maintenance of therapeutically effective amounts. These diagnostic methods can also be used to diagnose physiological disorders that result from abnormal levels of SBP.